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<DIV CLASS="navbar"><A HREF="http://vt100.net/"><IMG CLASS="button" SRC="vt100.net-logo.png" ALT="VT100.net" HEIGHT="16" WIDTH="102"></A> VT102 User Guide<TABLE WIDTH="100%">
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<TD ALIGN="LEFT"><A HREF="chapter6.html">Chapter 6</A></TD>
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<TABLE ID="T6-7" CLASS="majortable" FRAME="VOID" RULES="GROUPS" CELLSPACING="0" CELLPADDING="4" BORDERCOLOR="#ffffff">
<CAPTION>Table 6-7 Asymmetric Full-Duplex with Modem Control (FDX C) Signals</CAPTION>
<THEAD>
<TR VALIGN="BOTTOM">
<TH>Pin</TH>
<TH>Name (Mnemonic)</TH>
<TH>CCITT&nbsp;/ EIA</TH>
<TH>Switch</TH>
<TH>Description</TH>
</TR>
</THEAD>
<TBODY>
<TR VALIGN="TOP">
<TD>1</TD>
<TD>Protective ground<BR>(PGND)</TD>
<TD>101/AA</TD>
<TD>-</TD>
<TD>Connects to terminal chassis. Also connects to external ground through third wire of
power cord.</TD>
</TR>
<TR VALIGN="TOP">
<TD>3</TD>
<TD>Received data<BR>(RXD)</TD>
<TD>104/BB</TD>
<TD>-</TD>
<TD>To VT102:<BR>RXD receives serial characters from the computer.</TD>
</TR>
<TR VALIGN="TOP">
<TD>6</TD>
<TD>Data set ready<BR>(DSR)</TD>
<TD>107/CC</TD>
<TD>-</TD>
<TD>From VT102:<BR>When DSR is on:
<UL>
<LI>DSR indicator is on</LI>
<LI>Modem connects to a communication line</LI>
<LI>Modem is ready to use modem control signals.</LI>
</UL>
When DSR is off:
<UL>
<LI>DSR indicator is off</LI>
<LI>Terminal performs a disconnect.</LI>
</UL></TD>
</TR>
<TR VALIGN="TOP">
<TD>7</TD>
<TD>Signal ground<BR>(SGND)</TD>
<TD>102/AB</TD>
<TD>-</TD>
<TD>SGND is common ground reference potential for all connector signals except protective
ground. SGND connects to protective ground conductor.</TD>
</TR>
<TR VALIGN="TOP">
<TD>8</TD>
<TD>Receive line signal detector<BR>(RLSD)</TD>
<TD>109/CF</TD>
<TD>-</TD>
<TD>To VT102:<BR>Also called carrier detect, RLSD is on when communication line signals
are good enough to transfer data. When off, data received is ignored.</TD>
</TR>
<TR VALIGN="TOP">
<TD>13</TD>
<TD>Secondary clear to send<BR>(SCTS)</TD>
<TD>121/SCB</TD>
<TD>S3</TD>
<TD>To VT102:<BR>When switch S3 is on (closed), SCTS indicates when modem is ready to
transmit data. When on, modem is ready to transmit data and CTS indicator is on. When
off, modem is not ready to transmit data and CTS indicator is off.</TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN="5"><P CLASS="note">NOTE: When S3 is on (closed), switch S2 must be off (open).</P></TD>
</TR>
<TR VALIGN="TOP">
<TD>14</TD>
<TD>Secondary transmit data<BR>(STXD)</TD>
<TD>118/SBA</TD>
<TD>S7</TD>
<TD>When switch S7 is closed, STXD transmits serial characters and breaks generated by
terminal. STXD is in mark state when no characters are transmitted.</TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN="5"><P CLASS="note">NOTE: When S7 is on (closed), switch S6 must be off (open).</P></TD>
</TR>
<TR VALIGN="TOP">
<TD>19</TD>
<TD>Secondary request to send<BR>(SRTS)</TD>
<TD>120/SCA</TD>
<TD>S8</TD>
<TD>To VT102:<BR>When switch S8 is closed, SRTS is on if terminal is on-line and off if
terminal is off-line.</TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN="5"><P CLASS="note">NOTE: Switch S5 must be off (open).</P></TD>
</TR>
<TR VALIGN="TOP">
<TD>20</TD>
<TD>Data terminal ready<BR>(DTR)</TD>
<TD>108.2/CD</TD>
<TD>-</TD>
<TD>From VT102:<BR>DTR is on when terminal is on-line and off when terminal is
off-line or performing a disconnect. When on, modem can usually answer calls
(modem auto answer option). When off, modem disconnects and does not
answer calls.</TD>
</TR>
<TR VALIGN="TOP">
<TD>23</TD>
<TD>Speed select<BR>(SPSD)</TD>
<TD>111/CH</TD>
<TD>S10</TD>
<TD>From VT102:<BR>SPSD is on when receive speed SET-UP feature selection is greater
than 600 baud. SPSD is off when speed is 600 baud or less.</TD>
</TR>
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<TD ALIGN="LEFT"><A HREF="chapter6.html">Chapter 6</A></TD>
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